Answer: a. Increasing the surface area for diffusion
Explanation:
When the air is inhaled through the nostrils, the air containing the oxygen the air diffuses inside the alveoli. The alveoli are the tiny sacs where air enters and exchange of gases takes place. From the alveoli the oxygen enters into the blood stream. The oxygen is utilized by the cells for respiration. The increase in network and number of the alveoli will increase the surface area for the diffusion of oxygen and hence, will speed up the respiration process.
Answer:
A. (exponential) population
The correct answer is: a. A site in DNA that recruits the RNA Polymerase
Promoters are regions of DNA molecule located near the transcription start codons of genes, usually upstream on the DNA with the function to initiate DNA transcription. Promoters contain specific DNA sequences (e.g. TATA boxes) that are binding sites for the enzyme RNA polymerase and transcription factors that recruit RNA polymerase. Transcription factors can regulate gene expression and act as activators or repressors depending on sequences that attach to specific promoters.